1. Field of the Invention
The present invention relates to headwalls for drain pipes and, more particularly, to sectional headwalls for drain pipes.
2. Description of the Prior Art
The term xe2x80x9cheadwallxe2x80x9d or xe2x80x9cend wallxe2x80x9d typically refers to a reinforced concrete structure that supports one end of a pipe, such as a drain pipe, and retains earth fill on one side of the structure. The usual technique for constructing concrete headwalls involves the manual preparation of forms made typically of wood or metal and built at the intended headwall location. The forms are stripped away from the concrete after the headwall is formed. The forms are temporary in nature and require a significant amount of labor expense for carpentry and other trades necessary for the manual erection of these forms. Several trips to the headwall construction site are generally required before the concrete headwall is complete.
This prior art headwall construction method has other numerous disadvantages. For example, the headwall construction site is often located in an inaccessible or undeveloped area. The wooden forms most often used to construct the concrete headwall are typically made of heavy wooden planks and plywood sections that are nailed together and are difficult, in practice, to erect in these areas. The forms must be stabilized with timbers, boards and stakes that are driven into the ground at the construction site. This can be difficult, time consuming and labor-intensive at undeveloped sites. In addition, paper or another similar material must be positioned around the drain pipe, which extends through the forms to prevent concrete seepage and loss when the forms are filled with concrete. There is usually a pronounced gap in the area around the drain pipe because of the paper positioned around the drain pipe while the concrete cures. Furthermore, the forms must be greased to facilitate their removal after the concrete has hardened. Finally, the poured concrete must be vibrated to remove air voids and the surface of the concrete, when hardened, must be smoothed to remove imperfections left by the forms.
Over the years, attempts have been made to improve the xe2x80x9ctraditionalxe2x80x9d prior art method of constructing concrete headwalls discussed hereinabove. For example, U.S. Pat. No. 1,098,766 to Scully et al. discloses a bank retainer for a culvert pipe formed of a plurality of sheet metal plates that are bolted together. In operation, a bottom section of the bank retainer is placed below the culvert pipe and an upper section placed above the culvert pipe. The two sections are then bolted together. Once the sheet metal, box-like structure of the bank retainer is formed, the interior of the bank retainer is filled with earth through an opening in the front of the bank retainer. U.S. Pat. No. 1,664,503 to Cornell discloses a bulkhead wall for a culvert pipe that includes a series of metal front plates that surround the culvert pipe. The front plates have braces that extend outward into the backfill located behind the bulkhead wall. U.S. Pat. No. 3,779,021 to Green discloses a method of forming a concrete headwall that includes the use of prefabricated forms for concrete. The forms are removable after formation of the concrete headwall.
A more recent attempt to improve the traditional method discussed previously is disclosed by U.S. Pat. No. 4,723,871 to Roscoe. The Roscoe patent discloses a shell-like retainer structure for forming headwalls. The shell-like retainer structure includes two spaced apart plates that each define a U-shaped opening. The plates are centered over a drain pipe with the U-shaped opening defined by the respective plates cooperating with the drain pipe. After the plates are centered over the drain pipe, the structure is filled with earth through an opening formed in the top of the structure.
While each of these references attempts to improve upon the traditional method of forming concrete headwalls, several of the devices disclosed by these references are as heavy, bulky, and labor-intensive to use as the concrete forms used in the traditional method. In addition, these devices generally do not provide flexibility in adjusting the height of the headwall. The prior art devices discussed hereinabove typically provide a headwall of a given height that is defined by the height of the device. These devices generally do not provide the ability to alter the height of the headwall in accordance with design parameters for the headwall, such as the terrain at the intended location of the headwall, the amount of backfill that must be retained by the headwall, and the size of the drain pipe that is to be used with the headwall. This is a distinct disadvantage because it is common in the art to design the headwall at the construction site without the benefit of engineering the headwall in advance.
Consequently, it is an object of the present invention to provide a headwall that has an adjustable height that may be quickly and easily altered to suit the particular design criteria at the headwall construction site. It is a further object of the present invention to provide a headwall that overcomes the disadvantages of the traditional method of forming concrete headwalls.
The above objects are accomplished with a headwall assembly and a method of constructing a headwall in accordance with the present invention. The headwall assembly is intended to support a drain pipe. The headwall assembly, according to one embodiment of the present invention, includes a unitary base member, an annular drain pipe adapter, and a unitary lid member. The base member has two longitudinal walls and two end walls, which define an opening extending through the base member for receiving filler material into the base member. The base member further includes a sleeve extending between and connecting the longitudinal walls. The sleeve defines an aperture extending through the longitudinal walls. The drain pipe adapter is configured to be received in the sleeve and has an inner diameter sized to receive the drain pipe. The lid member is configured to engage a top end of the base member and enclose the top end of the base member.
The sleeve connecting the longitudinal walls of the base member may include a flange extending outward from one of the longitudinal walls. The flange may extend outward circumferentially around the aperture except in the area of a keyway recess defined by the flange. The drain pipe adapter may include a lip member configured to cooperate with the flange for connecting the drain pipe adapter to the base member. The lip member of the drain pipe adapter and the flange extending from the sleeve may be configured to be connected together with mechanical fasteners.
The drain pipe adapter may include a projection formed integrally with the lip member. The projection may be configured to cooperate with the keyway recess for preventing rotational movement of the drain pipe adapter relative to the base member when the drain pipe adapter is inserted into the sleeve. The drain pipe adapter may include a flange extending from the lip member. The flange extending from the lip member may be configured to be connected directly to the drain pipe with mechanical fasteners.
The longitudinal walls of the base member may be connected together by a plurality of cone shaped connectors extending from one of the longitudinal walls to the opposing longitudinal wall. The cone shaped connectors may define cone shaped recesses in the surface of the longitudinal wall. The headwall assembly may further include a plurality of cone shaped plugs configured to engage the recesses defined by the connectors.
The top end of the base member may define a circumferentially extending recess and the lid member may include a depending lip configured to engage the recess such that the lid member snap fits onto the base member.
The base member, the drain pipe adapter, and the lid member may be made of plastic. The lid member may include integrally formed projections for attaching light reflectors to the lid member.
The headwall assembly may further include a unitary wall member configured for attachment to one of the end walls of the base member. The wall member may be formed by two longitudinal walls and two end walls that define an opening extending through the wall member for receiving filler material into the wall member. At least one of the end walls of the wall member and at least one of the end walls of the base member are preferably configured to connect together with a tongue-in-groove connection. A second lid member may be provided to be positioned on top of and engage a top end of the wall member to enclose the opening extending through the wall member. The second lid member may be used to replace the lid member configured to engage the top end of the base member, with the second lid member formed to engage the top end of the base member and the top end of the wall member to enclose the respective openings defined through the base member and the wall member.
The headwall assembly may include a pair of wall members each configured to connect to one of the end walls of the base member. The end walls of the wall members may be configured to connect to the end walls of the base member with tongue-in-groove connections. The wall members may also be made of plastic.
The headwall assembly of the present invention may further include a sectional member provided between the base member and the lid member. The sectional member is configured to engage the top end of the base member. The lid member, in this embodiment of the present invention, is configured to engage a top end of the sectional member to enclose the top end of the sectional member. The sectional member is defined by two longitudinal walls and two end walls. The longitudinal walls and end walls define an opening extending through the sectional member that cooperates with the opening extending through the base member for receiving filler material into the headwall assembly. The sectional member may be made of plastic.
The top end of the base member may define a circumferentially extending recess and the sectional member may include a depending lip configured to engage the recess defined in the base member such that the sectional member snap fits onto the base member. The top end of the sectional member may also define a circumferentially extending recess and the lid member may include a depending lip configured to engage the recess defined in the sectional member such that the lid member snap fits onto the sectional member.
The unitary wall member, discussed previously, may be configured for attachment to a common end wall of the headwall assembly formed by the end walls of the base member and sectional member when the sectional member is placed on top and in engagement with the base member. At least one of the end walls of the wall member and at least one of the common end walls of the headwall assembly are preferably configured to connect together with a tongue-in-groove connection.
The present invention is also a method of constructing a headwall, including the steps of: providing a headwall assembly comprised of a base member and a lid member, with the base member having a ground engaging edge for engaging the ground; positioning the base member in engagement with the ground along the ground engaging edge of the base member, with the base member having two longitudinal walls and two end walls defining an opening extending through the base member, and with the base member having a sleeve extending between and connecting the longitudinal walls, with the sleeve defining an aperture extending through the longitudinal walls; extending a drain pipe through the aperture defined by the sleeve; filling the opening in the base member with filler material; and positioning the lid member on the base member such that the headwall is formed and a top end of the base member is enclosed.
The headwall assembly may further include the sectional member, discussed previously, which is configured to engage the top end of the base member. The method may further include the steps of: placing the sectional member in engagement with the top end of the base member, with the sectional member including two longitudinal walls and two end walls defining an opening extending through the sectional member and cooperating with the opening defined by the base member; and positioning the lid member on top of the sectional member such that the headwall is formed and a top end of the sectional member is enclosed.
The headwall assembly may further include the drain pipe adapter discussed previously, which is configured to be received in the sleeve connecting the longitudinal walls of the base member. When the drain pipe adapter is used with the headwall assembly, the method may include the steps of: inserting the drain pipe adapter into the sleeve; and extending a drain pipe through the drain pipe adapter.
As set forth previously, the sleeve connecting the longitudinal walls of the base member may include the flange extending outward from one of the longitudinal walls of the base member. The flange extends circumferentially around the aperture defined by the sleeve except in the area of the keyway recess defined by the flange. The lip member of the drain pipe adapter is preferably configured to cooperate with the flange, with the lip member having the integrally formed projection configured to cooperate with the keyway recess. The method may further include the step of inserting the drain pipe adapter into the sleeve such that the lip member cooperates with the flange and the projection is received in the keyway recess thereby preventing rotational movement of the drain pipe adapter relative to the base member.
The present invention is further directed to a wall member for use in constructing earth retaining walls and like structures. The wall member is comprised of a rectangular shaped unitary shell member defined by two longitudinal walls and two end walls. The longitudinal walls and end walls define an opening extending through the shell member for receiving filler material into the shell member. The end walls of the shell member are configured to connect to the end walls of additional wall members to form the earth retaining wall.
The shell member may include internal partitions defining a plurality of chambers within the shell member for receiving filler material. The end walls of the shell member may be configured to connect to the end walls of the additional wall members through a tongue-in-groove connection. At least one of the longitudinal walls of the shell member may be configured to connect to the end wall of one of the additional wall members. The shell member may be made of plastic.
Further details and advantages of the present invention will become apparent from the following detailed description read in conjunction with the drawings, wherein like parts are designated with primed reference numerals throughout.